Allow omitting optional parameters for Extensions API functions

chrome/common/extensions/api/experimental.app.json

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 [
   {
     "namespace":"experimental.app",
     "functions": [
       {
         "name": "notify",
@@ skipping 58 matching lines @@
             }
           },
           {
             "type": "function",
             "name": "callback",
             "optional": true,
             "description": "A callback when the function is complete. Any errors will be reported in <a href='extension.html#property-lastError'>chrome.extension.lastError</a>.",
             "parameters": []
           }
         ]
-      },
-      {
-        "name": "setLaunchIcon",
-        "nodoc": true,
-        "type": "function",
-        "parameters": [
-          {
-            "type": "object",
-            "name": "details",
-            "optional": true,
-            "properties": {
-              "extensionId": {
-                "type": "string",
-                "optional": true,
-                "description": "An optional id to do notifications for an app other than the calling app. This is just to allow prototyping with an extension that sends notifications on behalf of apps that don't support notifications yet; this will be removed before the API becomes stable."
-              }
-            }
-          },
-          {
-            "type": "object",
-            "name": "iconData",
-            "isInstanceOf": "ImageData",
-            "optional": true,
-            "additionalProperties": { "type": "any" },
-            "description": "Pixel data for an image to replace the launch icon on the New Tab Page. Must be an ImageData object (for example, from a canvas element). See http://code.google.com/chrome/webstore/docs/images.html for more details."
-          },
-          {
-            "type": "function",
-            "name": "callback",
-            "optional": true,
-            "description": "A callback when the function is complete. Any errors will be reported in <a href='extension.html#property-lastError'>chrome.extension.lastError</a>.",
-            "parameters": []
-          }
-        ]
-      },
-      {
-        "name": "resetLaunchIcon",
-        "nodoc": true,
-        "type": "function",
-        "description": "Resets the app's launch icon to its default value as specified in the manifest.json file.",
-        "parameters": [
-          {
-            "type": "object",
-            "name": "details",
-            "optional": true,
-            "properties": {
-              "extensionId": {
-                "type": "string",
-                "optional": true,
-                "description": "An optional id to do notifications for an app other than the calling app. This is just to allow prototyping with an extension that sends notifications on behalf of apps that don't support notifications yet; this will be removed before the API becomes stable."
-              }
-            }
-          },
-          {
-            "type": "function",
-            "name": "callback",
-            "optional": true,
-            "description": "A callback when the function is complete. Any errors will be reported in <a href='extension.html#property-lastError'>chrome.extension.lastError</a>.",
-            "parameters": []
-          }
-        ]
       }
     ]
   }
 ]